Winnies friend marco guessed that her riddle was about the number 79 Why can't 79 be the answer to Winnies riddle

8 answers

If you think about this question:

Winnie wrote the following riddle:
I am a number between 60 and 100.
My ones digit is two less than my tens digit.
I am a prime number.

Part A
What number does Winnie’s riddle describe?
Explain.

Part B
Winnie’s friend Marco guessed that her riddle was about the number 79.
Why can’t 79 be the answer to Winnie’s riddle?
Explain.

Then:

Part A

The digit in the tens place must be 6, 7, 8, or 9.

So the number must be:

64
becouse oness digit 4 is two less than tens digit 6

75
becouse oness digit 5 is two less than tens digit 7

86
becouse oness digit 6 is two less than tens digit 8

and

97
becouse oness digit 7 is two less than tens digit 9

Since 64 and 86 are even, they are divisible by 2.

Since 75 has a 5 in the ones place it is divisible by 5.

So 64, 75, and 86 are not a prime numbers.

Since the only factors of 97 are 1 and 97, 97 is a prime number.

Part B

Although 79 is a prime number between 60 and 100, the ones digit is two more than the tens digit.

The ones digit should be two less than the tens digit.
This helped me with my homework soooo much I'm studying for a test to so thanks for giving an explanation because now I get it and I will know how to do it on the test. Thank you for the help and also do you go to " Hawkins Elementary school" byyyyyyyeeeee. Also just because, HIT OR MISS!!!!!!!!!!!!!!
The answers were the right one thank you
tanks a lot I was struggling to help my sister o d this problem but you made it easy
Oh my gosh, at first I was struggling with this problem and you made it a whole lot easier! Other websites didn't explain it so I'm very glad to see this! Good job and keep up the good work.
I still don't get it how do you know the digits in the the tens place has to be 6, 7, 8, 9, ?
I am trying to do a test!
It wasn't the right answer sadly 😕 :[